Flu Facts

Influenza, or the flu, is a respiratory infection caused by a variety of flu viruses. The U.S. Centers for Disease Control and Prevention (CDC) estimates that 35 to 50 million Americans come down with the flu during each flu season, which typically lasts from November to March. Children are two to three times more likely than adults to get sick with the flu, and children frequently spread the virus to others. Although most people recover from the illness, CDC estimates that in the United States more than 100,000 people are hospitalized and more than 20,000 people die from the flu and its complications every year.

When and Where Do People Usually Get the Flu?
Flu outbreaks usually begin suddenly and occur mainly in the late fall and winter. The disease spreads through communities creating an epidemic. During the epidemic, the number of cases peaks in about three weeks and subsides after another three or four weeks. Half of the population of a community may be affected. Because schools are an excellent place for flu viruses to attack and spread, families with school-age children have more infections than other families, with an average of one-third of the family members infected each year.

How is the Flu Transmitted?
You can get the flu if someone around you who has the flu coughs or sneezes. You can get the flu simply by touching a surface like a telephone or door knob that has been contaminated by a touch from someone who has the flu. The viruses can pass through the air and can enter your body through your nose or mouth. If you've touched a contaminated surface, they can pass from your hand to your nose or mouth.
You are at the greatest risk of getting infected in highly populated areas, such as in crowded living conditions and in schools.

Are There Different Types of Flu Viruses?
The first flu virus was identified in the 1930's. Since then, scientists have classified flu viruses into types A, B, and C.

Type A is the most common and usually causes the most serious epidemics. Type B outbreaks also can cause epidemics, but the disease it produces generally is milder than that caused by type A. Type C viruses, on the other hand, never have been connected with a large epidemic.

What are Possible Complications from the Flu?
You can have flu complications if you get a bacterial infection, which causes pneumonia in your weakened lungs. Pneumonia also can be caused by the flu virus itself.

Symptoms of complications will usually appear after you start feeling better. After a brief period of improvement, you may suddenly get:

• High fever
• Shaking chills
• Chest pain with each breath
• Coughing that produces thick, yellow-greenish-colored mucus

Pneumonia can be a very serious and sometimes life-threatening condition. If you have any of these symptoms, you should contact your doctor immediately so that you can get the appropriate treatment.

Are There Other Flu Complications that Only Affect Children?
Reye's syndrome, a condition that affects the nerves, sometimes develops in children and adolescents who are recovering from the flu. Reye's syndrome begins with nausea and vomiting, but the progressive mental changes (such as confusion or delirium) cause the greatest concern.

The syndrome often begins in young people after they take aspirin to get rid of fever or pain. Although very few children develop Reye's syndrome, you should consult a doctor before giving aspirin or products that contain aspirin to children. Acetaminophen does not seem to be associated with Reye's syndrome.

Other complications of the flu that affect children are:
• Convulsions caused by fever
• Croup
• Ear infections, such as otitis media

Newborn babies recently out of intensive care units are particularly vulnerable to suffering from flu complications.

Source: National Institute of Allergy and Infectious Diseases